Running GB1 in Higher Freq's

G'day Ismael,

It would seem from your sled tests that running our GPM's in GB1 with larger coils such as an 18\"DD coil in Pos.2 we might NOT loose as much sensitivity on small nuggets as I would have expected.

What are your thoughts of say running my old (dustbin) 18\" Mono in GB1 in Pos.3 or dare I say Pos.4 Therefore in GB1 it should run quieter or smoother with depth and in higher freq's give it added sensitivity?

The reason I ask this question is a while back I had my 20cent diameter size nugget sitting at the bottom of a deep hole and I heard it clearly in GB- Search(midway) , Pos.4 with my 18\"DD but NOT in Pos.1,2 or 3 to my surprise.

All other mods were flat out but as soon as I moved the coil away over undug ground it was too noisy in Pos.4

I only wish I had tried it in GB1 in Pos. 4 at the time.

Yours Detecting,
GaryQ

Ismael,

Yes it sure had me stumped at that time also. I had decided to do an in-ground test in hot ground where I had previously found my 1st nugget with your GP mod. a 6.8 grammer at 10\" with 11\"DD. It is the one I am holding up in closeup of my photo as Author.

Re-digging this hole on another trip I bored a hole at a angle downwards for my largest nugget to slide down and tested it with my CT 18\"DD. BTW the nugget weighs 2.5ozs with a 30mm diameter.

The best I could get it at in-ground was 14\" in Pos.3 with both Gain full-on at max volts which disappointed me for its weight although it is not flat but roundish in shape.

It was later that day and out of curiosity after I dug a deep hole on a piece of rubbish that I threw the 2.5oz nugget back in this hole which I measured at 16\"

Playing with different freq. settings I found that only Pos.4 picked up the nugget in the hole for some reason. Maybe battery voltage was lower at this timer? But as I said as soon as I moved back over ground detector was too noisy so I switched back to Pos.3

Apart from above I have since found that the 18\"DD sometimes won't run at all in Pos.4

A recent in- ground test through the wall of an old timers pothole using two larger Native Copper pieces of 3oz and 30ozs I found as you say the lower Freqs. are the way to go with bigger coils. It was Pos.2 with the 18\"DD and all other mods. flat out which was the best setting this time.

Just for the record the 18\"DD clearly heard the flat 3oz piece at 20\" and the squarish 30oz piece at 26\" however I ran out of puff trying to tunnel deeper with this piece as damn ground was hard rock rubble packed in whitish clay. Boy those old Prospectors worked hard.

I am hoping to return to pothole again and do further tests with same settings BUT in GB1

As to my problem of Freq. Drift I was out last weekend and my GPM ran as sweet as.

I have attached a photo of my recent in-ground test and another of targets I test with. Did not test the largest 40oz copper piece in- ground as to big of a darn hole to tunnel.

Cheers,
GaryQ

I would like to know what the symptoms of frequency drift are, what does it sound like.

Ted,

Ismeal gave the phrase of \"frequency drift\" to the hick- up with my 2000.

What I found was sometimes if I bumped the coil my threshold level would suddenly change pitch and I would have to switch off the machine and restart to re-set it again.

Ismael had enquired if the problem existed in all freq. however I was not sure as I have been mainly running both my DD's in Freq. 3

As I said all was well on my last trip but if it occurs again I will shift through all the frequencies instead of switching off to see if it settles again.

GaryQ.

Just some more results on my In-Ground Test hole on the left in my photo above.

Had an opportunity to run my CT18\"DD on my mates 2200 with 7.3 volt system over my 3oz copper piece and In -Ground Test hole which I had dug inwards and downwards at an angle to a measured depth.

When placed inside the hole where I could clearly hear it with my 2000GPM in Pos.2 at a measured 20\" and still lift coil 2\" above ground level before signal vanished, I was unable to identify signal enough with the 2200 even at ground level. Trying all different settings on the 2200 to bring the 3oz piece in I still could not hear it.

I was somewhat surprised as Air- Tests with the 18\"DD on the 2200 in Deep setting equalled my GPM in Pos. 2 at 20.5\"

I had also Air-Tested the 3oz piece with a 3000 and NF16\"DD to 19.5\" and I am busting to try the 3000 over my test hole with my 18\"DD.